Further tailoring of material properties in non-equimolar aluminium titanate ceramic materials

The authors started their R&D activities related to aluminium titanate (AT) ceramics in the early 1990s by addressing the critical problems of aluminium titanate, such as thermodynamical instability and micro-cracking. After that, their focus has permanently been on improving, optimizing and tailoring the properties of the aluminium titanate ceramic materials produced by reaction-sintering of equimolar mixtures of alumina and titania powders. This paper presents their latest investigations on AT ceramics produced by reaction-sintering of non-equimolar mixtures of the two main components. The objective of these investigations has been to emphasize the effects of excesses of either alumina or titania on the internal stresses build up in these materials and the consequences these internal stresses could have on some material properties which are most important for the industrial applications of AT ceramics. The ways and the extent in which these internal stresses could be controlled/managed were investigated, with the ultimate goal of expanding the possibilities for further tailoring the thermo-mechanical properties of the aluminium titanate ceramics, so that they meet specific application requirements.